JPH10297798A - Sheet discharging mechanism for image forming device, and image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sheet discharging mechanism in which an image-recorded sheet can be stacked on a sheet discharging part in an FD (a feed down) direction without requiring a large installation space in a main body of an image forming device. SOLUTION: In the case where an FD direction is selected as a stacking direction for a recording sheet P, a turn guide plate 31 is oscillated from a stand-by position apart from the recording sheet P to an illustrated guide position at a timing when the recording sheet P reaches a position right before a sheet discharge roller pair 11. The recording sheet P discharged from a sheet discharge guide passage 9 by the sheet discharge roller pair 11 is applied to a guide surface 31b to be curved in a roughly U-shaped form along the guide surface 31b, and it slides to the guide surface 31b extended toward a sheet discharge part 33. The recording sheet P is thus guided in such a way that its tip part is stacked on the sheet discharge part 33, and its surface is inverted in such a way that a stacking direction on the sheet discharge part 33 is the FD direction.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a discharge device which conveys a sheet on which an image has been recorded in an image forming apparatus such as a printer device or a facsimile device so as to be stacked from a plurality of discharge portions to a preselected discharge portion. The present invention relates to a paper mechanism and an image forming apparatus including the paper discharge mechanism.

[0002]

2. Description of the Related Art FIG. 9 is a block diagram of an image forming apparatus provided with a conventional paper discharge mechanism. This image forming apparatus has a printer function for forming an image on a sheet based on image information input from the outside, and a document. A scanner function for reading an image and a control unit (not shown) connected to a public line such as a telephone line have a transmission / reception function of inputting / outputting image information via the public line. Therefore, the illustrated image forming apparatus can be used as either a printer or a facsimile machine according to a user's request.

Reference numeral 1 denotes an apparatus main body of the image forming apparatus, 2 denotes a process cartridge configured as a replacement part for the apparatus main body 1, 3 denotes a photosensitive drum arranged in the process cartridge 2, and the process cartridge 2 The omitted cleaning device, developing device, charging device, and the like are arranged so as to surround the photosensitive drum 3. Reference numeral 4 denotes an optical writing unit that scans the photosensitive drum 1 charged to a predetermined potential based on image information with a laser beam and forms an electrostatic latent image on the photosensitive drum 3, and 5 is in contact with the photosensitive drum 3. It is a transfer roller. Here, the electrostatic latent image formed on the photosensitive drum 3 is developed into a toner image by a developing device, and the transfer roller 5 transfers the toner image onto the recording paper P at a transfer position where the recording paper P is sandwiched together with the photosensitive drum 3. Transcribe.

Reference numeral 6 denotes a paper feed cassette which is detachably attached to the lower portion of the apparatus main body 1 and stores the recording paper P. Reference numeral 7 denotes a paper feeder which separates and feeds the recording paper P stored in the paper feed cassette 6 one by one. The recording paper P, which is a paper roller and separated and fed by the paper feed roller 7, is conveyed to a transfer position along a paper feed guide path 8 constituted by a guide plate or the like. Reference numeral 9 denotes a paper discharge guide path formed by a guide plate or the like, which extends from the transfer position in the paper discharge direction. A fixing device 10 is disposed in the middle of the paper discharge guide path 9 to fix the toner image by heating and pressing the recording paper P on which the toner image is formed, and a fixing device 11 is disposed at the end of the paper discharge guide path 9. A discharge roller pair for discharging the recording paper P on which the toner image has been fixed by the fixing device 10 from the discharge guide path 9, and a recording paper P discharged by the discharge roller pair 11.
Is a paper discharge tray on which is stacked.

Reference numeral 20 denotes a scanner unit for reading an image formed on a document. In the scanner unit 20, reference numeral 21 denotes a document loading unit for loading a bundle of documents (not shown), and reference numeral 22 denotes a document loading unit. A separation paper feed mechanism that separates and feeds one document from the bundle of documents loaded in the document 21. Reference numeral 23 scans a document that is separated and fed by the separation paper feed mechanism 22 and conveyed in the main scanning direction by a pair of conveyance rollers. A sensor unit 24 for reading an image is a paper output tray on which the originals from which the image is read are stacked.

[0006]

In an image forming apparatus used for multiple functions in response to a user's request, the recording paper P is stacked on a paper discharge unit with the image surface of the recording paper P facing downward (in the FD direction). May be requested. For example, when an image is formed on a plurality of recording sheets P based on image information that is continuous over a plurality of pages, it is more convenient to stack the recording sheets P on which images have been formed in the FD direction where there is no need to rearrange the images. .

However, in the image forming apparatus configured as shown in FIG. 9, in order to enable the recording paper P to be stacked in the FD direction, the recording paper P on which the image is formed is conveyed while the surface is reversed. A reversing unit is required. Since such a reversing unit is usually constituted by a plurality of members such as a guide path curved substantially U-shaped and a pair of rollers arranged along the guide path, a considerably large installation space is required. . Further, it is necessary to add to the apparatus main body 1 a paper discharge unit dedicated to receiving the recording paper P discharged from the reversing unit. Such a paper discharge unit is usually provided on the upper surface of the apparatus main body 1 or inside the apparatus main body 1. However, in order to realize a function as a facsimile apparatus, a scanner unit 20 is disposed on the upper part of the apparatus main body 1 as shown in the figure. In such a configuration, it becomes difficult to provide a paper discharge unit for the reversing unit on the upper surface of the apparatus main body 1. Further, when a paper discharge unit for a reversing unit is provided inside the apparatus main body 1,
Since the guide path and the like are arranged in the apparatus main body 1, the space use efficiency is deteriorated, and there is a problem that the apparatus main body 1 is enlarged.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a paper discharge mechanism capable of stacking paper on which an image has been recorded in a paper discharge direction in an FD direction without requiring a large installation space in a main body of the image forming apparatus, and a paper discharge mechanism. An object of the present invention is to provide an image forming apparatus provided with a paper mechanism.

[0009]

According to a first aspect of the present invention, there is provided a paper discharge mechanism connected to a recording unit in a main body of an image forming apparatus, and a paper discharge mechanism extending from the recording unit in a paper discharge direction. An extending paper ejection guide path, a conveying means for conveying the paper on which an image has been formed by the recording section along the paper ejection guide path, and a sheet discharged from the paper ejection guide path by the conveying means. In a paper ejection mechanism of an image forming apparatus having a paper ejection unit to be stacked, a paper ejection unit protruding to the outside from the main body of the image forming apparatus, and a standby position to be separated from a sheet being conveyed by the conveyance unit. A turn guide plate movably supported at a guide position for guiding the sheet conveyed by the conveying means, and the sheet held at the standby position when the sheet is ejected from the sheet ejection guide path. Turn the turn guide plate Is moved to de position, after being surface inversion with guides the sheet being conveyed in the sheet discharge portion by the conveying means by the guide surface of the turn guide plate,
And a drive unit for returning the turn guide plate to the standby position and separating the paper discharged from the paper stacked on the paper discharge unit in a FD (Face Down) direction with the image surface facing downward on the paper discharge unit. .

According to the paper discharging mechanism of the first aspect, the paper discharging portion protruding from the inside of the main body of the image forming apparatus to the outside and the turn guide plate movably supported at the standby position or the guide position. The driving means moves the turn guide plate held at the standby position to the guide position when the paper is discharged from the paper discharge guide path, and is conveyed by the conveying means by the guide surface of the turn guide plate. After guiding the paper to the paper discharge unit and reversing the surface, the turn guide plate is returned to the standby position and separated from the paper stacked on the paper discharge unit in the FD direction, thereby forming a guide curved substantially U-shaped. Without using a reversing unit composed of a plurality of members such as roads and roller pairs,
Sheets can be stacked on the paper discharge section in the D direction, and a part of the FD paper discharge section is disposed in the apparatus main body, so that the length of the paper discharge section protruding from the apparatus main body is suppressed. You.

Further, according to a second aspect of the present invention, in the image forming apparatus according to the first aspect, the sheet conveyed by the conveying means by the guide surface is guided to the sheet discharging portion and the surface is reversed. Then, the turn guide plate is returned from the guide position to the guide position, and the guide surface is moved in a direction in which the guide surface is released from the rear end curved portion of the sheet so as to be separated from the sheet stacked on the sheet discharge unit. The rear end of the sheet separated from the turn guide plate is projected outside the main body of the image forming apparatus.

According to the second aspect of the present invention, after the paper being conveyed by the conveying means by the guide surface is guided to the paper discharge section and the surface thereof is turned over, the turn guide plate is moved from the guide position. While returning to the standby position, the guide surface is moved in a direction to escape from the rear-end curved portion of the sheet to separate from the sheet stacked on the sheet discharging section, and the rear end of the sheet separated from the turn guide plate is moved to the apparatus body. The paper is fed out of the paper discharge guide path and the curvature radius of the curved portion is allowed to change naturally, so that the paper is bent or the curved portion of the paper is restored to a flat shape. The repulsive force at this time prevents the paper stacking position in the paper discharge unit from being disturbed, and the paper is stacked on the paper discharge unit with the rear end of the paper protruding outside the apparatus main body.

According to a third aspect of the present invention, in the paper discharging mechanism according to the first or second aspect, the paper discharging unit is detachably mounted on a main body of the image forming apparatus and stores paper. It is provided on the upper surface of the cassette.

According to the paper discharge mechanism of the third aspect, the paper discharge section is provided on the upper surface of the paper feed cassette detachably mounted on the apparatus main body, so that the space in the apparatus main body can be efficiently used. Used FD paper with a small number of parts
There can be provided a paper discharge unit stacked in the direction.

According to a fourth aspect of the present invention, there is provided an image forming apparatus including the paper discharge mechanism according to the first, second, or third aspect, a printer function for forming an image on a sheet based on input image information, and a document image. It has a scanner function for reading and a transmission / reception function for inputting / outputting image information via a public line.

According to the image forming apparatus of the fourth aspect, the paper discharging mechanism of the first, second, or third aspect is applied to the image forming apparatus having a printer function and a scanner function, thereby discharging the paper. The paper discharged from the guide path can be stacked on the paper discharge unit in the FD direction.

[0017]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a configuration diagram of an image forming apparatus provided with a paper discharge mechanism according to an embodiment of the present invention.
Members corresponding to the members described with reference to FIG. 9 are denoted by the same reference numerals, and description thereof will be omitted. This image forming apparatus has the same printer function and function as the image forming apparatus shown in FIG.
It has a scanner function and a transmission / reception function, and can be used as either a printer device or a facsimile device according to a user's request.

Reference numeral 31 denotes a turn guide plate which is supported so as to be swingable about a support shaft 31a. The turn guide plate 31 receives the recording paper P discharged from the discharge guide path 9 and a discharge guide. A guide surface 31b for guiding the paper in a direction different from the paper discharge direction by the path 9 is formed. Reference numeral 32 denotes a FU (Face Up) discharge tray detachably mounted on an exterior panel of the apparatus main body 1, and reference numeral 33 denotes an FD (FD) provided on an upper surface of the sheet cassette 6 detachably mounted on the apparatus main body 1. The paper discharge portion 33 extends over a region protruding from the inside of the apparatus main body 1 to the outside on the upper surface of the paper feed cassette 6, and is provided with a stopper 33a. It is movably supported in the paper length direction of P.

An operation panel (not shown) is provided with a selection switch, which allows the user to move the image plane upward as a stacking direction of the recording paper P discharged from the paper discharge guide path 9. Any one of the aimed FU direction and the FD direction can be selected. FIG. 2 is an explanatory diagram of the operation of the paper discharge mechanism of the present embodiment when the FU direction is selected as the stacking direction. FIGS. 3 to 5 are the operations of the paper discharge mechanism of the present embodiment when the FD direction is selected as the stacking direction. FIG.

When the FU direction is selected as the stacking direction of the recording paper P by the selection switch, a driving mechanism 50 described later is used.
Holds the turn guide plate 31 at the standby position shown in FIG. At this time, the user attaches the paper ejection tray 32 to the apparatus main body 1 before image formation is started. The turn guide plate 31 holds the guide surface 31 by being held at the standby position.
b is separated from the recording paper P discharged from the discharge guide path 9. Accordingly, the recording paper discharged from the paper discharge guide path 9 by the paper discharge roller pair 11 which is a conveying means is guided by the paper discharge guide path 9 in the direction of the paper discharge tray 32, and the process cartridge 2, the transfer roller 5, etc. The image is formed on the paper output tray 32 with the image surface on which the toner image is formed by the recording unit having the FU direction.

When the FD direction is selected as the stacking direction of the recording paper P by the selection switch, the driving mechanism 50
Turns the turn guide plate 31 from the standby position to the guide position shown in FIG. 3 at the timing when one recording sheet P reaches a position slightly before the discharge roller pair 11. At this time, when the discharge tray 32 is mounted on the apparatus main body 1, the user detaches the discharge tray 32 from the apparatus main body 1 before image formation is started.

The recording paper P discharged from the discharge guide path 9
Is the guide surface of the turn guide plate 31 that has swung to the guide position.
It comes into contact with the guide surface 31b, curves substantially in a U-shape along the guide surface 31b, and slides on the guide surface 31b extending in the direction of the paper discharge unit 33. As a result, the recording paper P is guided so as to be stacked on the paper discharge unit 33, and the surface is reversed so that the stacking direction on the paper discharge unit 33 becomes the FD direction. The recording paper P is sent out from the paper ejection guide path 9 by the paper ejection roller pair 11 even after the leading end portion reaches the paper ejection part 33, and moves along the paper ejection part 33 to stop as shown in FIG. Abuts 33a.

On the other hand, the drive mechanism 50 returns the turn guide plate 31 from the guide position to the standby position just before the leading end of the recording paper P comes into contact with the stopper 33a. When the turn guide plate 31 returns to the standby position and separates from the recording paper P, the recording paper P is discharged from the discharge guide path 9 as shown in FIG.
And the curvature radius of the substantially U-shaped curved portion is reduced without being restricted by the guide surface 31b. Thereafter, the recording paper P whose rear end has come off from the paper discharge guide path 9
The substantially U-shaped curved portion falls onto the paper discharge unit 33 by its own weight, and is stacked on the paper discharge unit 33 with its rear end protruding outside the apparatus main body 1.

Here, the user preliminarily sets the position of the stopper 33a corresponding to the size of the recording paper P so that the rear end of the recording paper P stacked on the paper output unit 33 projects outside the apparatus main body 1. Is adjusted. When the turn guide plate 31 swings from the guide position to the standby position, the turn guide plate 31 is moved in a direction in which the guide surface 31b is released from the substantially U-shaped curved portion of the recording paper P as shown in FIG. Since the recording paper P is sent out from the paper discharge guide path 9 and the radius of curvature of the curved portion is allowed to change naturally, the recording paper P may be bent,
The stacking position of the recording paper P in the paper discharge unit 33 is prevented from being disturbed by the repulsive force when the curved portion of the recording paper P is restored to a planar shape.

FIGS. 7 and 8 are diagrams showing the configuration of a drive mechanism for the turn guide plate in the paper discharge mechanism of the present embodiment. FIG. 7 shows a state where the turn guide plate 31 is held at the standby position by the drive mechanism 50. FIG. 8 shows a state in which the drive mechanism 50 swings the turn guide plate 31 to the guide position. 51, 52, 53 and 54 are gears, respectively.
Of these, the gears 51, 52 and 53 constitute a gear train for rotating the paper discharge roller pair 11, and the gears 51, 52 and 54 constitute a gear train for swinging the turn guide plate 31. I have. Reference numeral 55 denotes a cam holding plate connected to the gear 54 via a clutch mechanism (not shown). On the outer peripheral surface of the cam holding plate 55 formed in a disk shape, hook claws 55 are provided at two predetermined positions.
a and 55b are protruding. 56 is a cam that is connected to the cam holding plate 55 and rotates or stops together with the cam holding plate 55, 57 is an electromagnetic solenoid for swinging the latch lever 58, and 59 detects that the turn guide plate 31 is at the standby position Position sensor.

In the driving mechanism 50 configured as described above,
When the drive motor (not shown) of the transport system is turned on,
The gears 51, 52, 53 and 54 always rotate in the direction of the arrow. At this time, the paper discharge roller pair 11 rotates in the direction of discharging the recording paper P from the paper discharge guide path 9 by the torque from the gears 51, 52, and 53, and the cam holding plate 55 causes the gears 51, 52, and 54 to rotate. Attempts to rotate counterclockwise due to torque from Also, cam 56
Is a follower surface 31c formed at the rear end of the turn guide plate 31.
7 and is held at the first phase shown in FIG. 7 in the rotation direction, thereby supporting the turn guide plate 31 at the standby position, and rotating from the first phase to the second phase shown in FIG. Thus, the turn guide plate 31 is configured to swing from the standby position to the guide position.

When the drive mechanism 50 is in the initial state shown in FIG. 7, the electromagnetic solenoid 57 is turned off and the latch lever 58 is supported at the latch position shown by the solid line. At this time, the locking lever 58 locks the locking claw 55a and stops the rotation of the cam holding plate 55 which is about to rotate in the counterclockwise direction.
And the clutch mechanism is turned off to stop the torque transmission, causing the gear 54 to idle. Therefore, when the user selects the FU direction as the stacking direction of the recording paper P by the selection switch, the driving mechanism 50 stops the cam 56 at the first phase and holds the turn guide plate 31 at the standby position.

On the other hand, when the user selects the FD direction as the stacking direction of the recording paper P by the selection switch, the drive mechanism 50 turns on the electromagnetic solenoid 57 for a certain period of time, and moves the latch lever 58 to the release position indicated by a chain line. To release the hooking on the hooking claws 55a. As a result, the clutch mechanism is turned on to transmit torque, and the cam holding plate 55 and the cam 56 are rotated counterclockwise. By turning off the electromagnetic solenoid 57 again after a certain period of time, the locking lever 58 swings to the locking position and comes into contact with the outer peripheral surface of the cam holding plate 55, and the locking claw 55b is released. After climbing over, the hook 55b is hooked, and the rotation of the cam holding plate 55, which is going to rotate counterclockwise, is stopped. As a result, the cam 56 is maintained at the second phase, and the clutch mechanism is turned off, causing the gear 54 to idle. Here, when the cam 56 rotates counterclockwise from the first phase and swings downward by its own weight, the turn guide plate 31 stops the rotation of the cam 56 in the second phase. Held in position.

Thereafter, the turn guide plate at the guide position
When returning the recording paper P to the standby position at the timing immediately before the leading end of the recording paper P contacts the stopper 33a on the paper discharge unit 33, the electromagnetic solenoid 57 is turned on for a certain period of time, and the latch lever 58 is indicated by a chain line. By swinging to the release position, the hooking to the hooking claws 55a is released, and the cam holding plate 55 and the cam 56 are rotated counterclockwise. By rotating the cam 56 in the second phase counterclockwise, the cam 56 presses the follower surface 31c to swing the turn guide plate 31 at the guide position upward. Immediately before the turn guide plate 31 returns to the standby position,
The striker 31d of the turn guide plate 31 turns on the position sensor 59. The drive mechanism 50 turns off the electromagnetic solenoid 57 at the timing when the position sensor 59 is turned on, and swings the locking lever 58 to the locking position. The cam 56 stops rotating in the first phase by the locking lever 58 swinging to the locking position locking the locking claw 55a, and the turn guide plate 31 returns to the standby position.

[0030]

As described above, according to the first aspect of the present invention,
According to the paper discharging mechanism described above, the paper discharging unit includes a paper discharging unit protruding from the inside of the main body of the image forming apparatus to the outside, and a turn guide plate movably supported at a standby position or a guide position, and When the paper is discharged from the guide path, the turn guide plate held at the standby position is moved to the guide position,
After the sheet conveyed by the conveying means is guided by the conveying means by the guide surface of the turn guide plate and is turned over, the turn guide plate is returned to the standby position, and the sheet is discharged in the FD direction downward toward the image surface. By separating the sheet from the sheet stacked on the sheet portion, the sheet is discharged in the FD direction by the turn guide plate without using a reversing unit constituted by a plurality of members such as a guide path and a pair of rollers curved substantially in a U-shape. Since the paper can be stacked on the paper unit, it is possible to provide a paper discharge mechanism that does not require a large installation space in the main body of the apparatus, and sets the paper stacking direction of the paper stacked on the paper discharge unit to the FD direction. Since a part of the FD discharge unit is arranged in the apparatus main body and the length of the discharge unit protruding from the apparatus main body is suppressed, it is possible to suppress an increase in the size of the image forming apparatus due to the FD discharge unit.

Further, according to the paper discharge mechanism of the present invention, after the paper being conveyed by the conveying means by the guide surface is guided to the paper discharge portion and the surface is reversed, the turn guide plate is moved from the guide position. Along with returning to the standby position, the guide surface is moved in a direction away from the rear end curved portion of the sheet to be separated from the sheet stacked on the sheet discharging section, and the rear end of the sheet separated from the turn guide plate is image-formed. By projecting the sheet outside the main body of the apparatus, the sheet is sent out from the sheet ejection guide path and the radius of curvature of the curved portion is allowed to naturally increase, so that the sheet is bent or the curved portion of the sheet is flat. The stacking position of the paper in the paper discharge unit is prevented from being disturbed by the repulsive force when the paper is restored to the original state, and the paper is stacked on the paper discharge unit with the rear end of the paper protruding outside the apparatus main body. In the user it becomes possible to visually recognize the sheets stacked on the paper discharge unit, it is possible to take out the bundle of sheets easily from the second discharge unit on.

Furthermore, according to the paper discharge mechanism of the third aspect, the paper discharge section is provided on the upper surface of the paper feed cassette detachably mounted on the apparatus main body, so that the space in the apparatus main body can be efficiently used. Used FD paper with a small number of parts
Can be provided, so that an increase in the size of the apparatus body and an increase in cost due to the FD discharge section disposed in the apparatus body can be suppressed.

Further, according to the image forming apparatus of the present invention, by applying the paper discharging mechanism of the present invention to an image forming apparatus having a printer function and a scanner function. Since the paper discharged from the paper discharge guide path can be stacked on the paper discharge unit in the FD direction, an image is formed when forming an image on a plurality of papers based on continuous image information over a plurality of pages. This eliminates the need to sort the paper sheets.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of an image forming apparatus including a paper discharge mechanism according to an embodiment of the present invention.

FIG. 2 is a diagram illustrating an operation when the FU direction is selected as a sheet stacking direction in the sheet discharging mechanism according to the embodiment of the present invention.

FIG. 3 is an explanatory diagram illustrating an operation when the FD direction is selected as a sheet stacking direction in the sheet discharging mechanism according to the embodiment of the present invention.

FIG. 4 is an operation explanatory diagram when the FD direction is selected as a sheet stacking direction in the sheet discharging mechanism according to the embodiment of the present invention;

FIG. 5 is an explanatory diagram of an operation when the FD direction is selected as a sheet stacking direction in the sheet discharging mechanism according to the embodiment of the present invention.

FIG. 6 is an explanatory diagram of an operation of the turn guide plate in the paper discharge mechanism according to the embodiment of the present invention.

FIG. 7 is a configuration diagram of a drive mechanism for a turn guide plate in the paper discharge mechanism according to the embodiment of the present invention.

FIG. 8 is a configuration diagram of a drive mechanism for a turn guide plate in the paper discharge mechanism according to the embodiment of the present invention.

FIG. 9 is a configuration diagram of an image forming apparatus including a conventional paper discharge mechanism.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Device main body, 2 ... Process cartridge, 3 ... Photoconductor drum, 5 ... Transfer roller, 6 ... Paper feed cassette,
9: discharge guide path, 31: turn guide plate, 31b: guide surface, 32: discharge tray, 33: discharge section, 33a: stopper, 50: drive mechanism, 51, 52, 53, 54: gear,
55… Cam holding plate, 56… Cam, 57… Electromagnetic solenoid,
58: Latch lever, P: Recording paper.

Claims (4)

[Claims] A discharge guide path connected to a recording unit in the main body of the image forming apparatus and extending from the recording unit in a paper discharge direction; and a sheet on which an image is formed by the recording unit. And a discharge unit on which the sheets discharged from the discharge guide path are stacked by the transfer unit. And a turn guide plate movably supported at a standby position separated from the paper being conveyed by the conveyance means or at a guide position for guiding the paper being conveyed by the conveyance means. When paper is discharged from the discharge guide path,
After moving the turn guide plate held at the standby position to the guide position, guide the sheet being conveyed by the conveying means by the guide surface of the turn guide plate to the paper discharge unit, and reverse the surface, Return the turn guide plate to the standby position and turn the FD (FaceD
a paper discharge mechanism of the image forming apparatus, comprising: driving means for separating the paper stacked on the paper discharge unit in the own) direction. 2. After the sheet conveyed by the conveying means is guided by the guide surface to the sheet discharging unit and the sheet is reversed, the turn guide plate returns from the guide position to the standby position. Moving the guide surface in the direction of releasing from the rear end curved portion of the sheet to separate the sheet from the sheet stacked on the sheet discharging portion, and moving the rear end of the sheet separated from the turn guide plate to the outside of the main body of the image forming apparatus. The paper ejection mechanism of an image forming apparatus according to claim 1, wherein the paper ejection mechanism protrudes. 3. The image forming apparatus according to claim 1, wherein the sheet discharging unit is provided on an upper surface of a sheet cassette that is detachably mounted on a main body of the image forming apparatus and stores sheets. Paper ejection mechanism. 4. A printer function for forming an image on a sheet based on input image information, a scanner function for reading a document image, and an image forming apparatus via a public line, comprising the sheet discharging mechanism according to claim 1, 2, or 3. An image forming apparatus having a transmission and reception function for inputting and outputting information.